The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Various software applications allow users to manually develop digital 3D models of various real-world objects. In general, users utilize various 3D shapes (such as cubes, spheres, and cones) to directly define 3D geometry or 2D shapes (such as circles, rectangles, and triangles) to define facets of the 3D geometry. Some software applications also permit users to texture 3D geometry using photographs or artificial patterns. Today, many users develop highly detailed models of landmark structures and apply real-world photographs of these landmark structures to the models as textures.
Meanwhile, digital imaging techniques have been developed to extract 3D geometry of a real-world object from sets of photographs of the object. According to one such technique, a system identifies a common feature depicted in multiple photographs captured from different positions and different camera orientations. The system then uses the common identified feature to derive points in the feature geometry as well as camera poses in a 3D coordinate system. In this manner, the system generates a “3D point cloud,” which also can be textured, to define an automatically extracted 3D model of the object.
A manually developed 3D model may describe a portion of the 3D geometry missing from an automatically extracted 3D model of the same real-world object, and the automatically extracted 3D model may describe some of the 3D geometry of the real-world object at a higher resolution that the manually developed 3D model. However, digital 3D models developed using these two different techniques exist in different coordinate systems and conform to different formats.